The t(6;9)(p23;q34) is a recurrent chromosomal abnormality observed in 1% of acute myelogenous leukemia (AML), which generates a fusion transcript between DEK and CAN/NUP214 genes. We used a DEK-CAN real-time quantitative (RQ)-PCR strategy to analyze 79 retrospective and prospective samples from 12 patients. Five patients reached DEK-CAN negativity (sensitivity 10 − 5 ); all underwent early allogeneic hematopoietic stem cell transplantation (median 5.5 months from diagnosis) with some demonstrating molecular positivity at the time of allograft. All four cases in CCR with adequate follow-up (median 18.5 months, range 13–95) demonstrate persistent molecular negativity, whereas all seven patients with persistent DEK-CAN positivity died at a median of 12 months from diagnosis (range 7–27). We conclude that DEK-CAN molecular monitoring by RQ-PCR in t(6;9) malignancies is a useful tool for individual patient management and that molecular negativity is indispensable for survival, but should not be a prerequisite for allografting in this rare, poor prognosis, subset of AML.

Hepatitis C virus (HCV) has been associated with the development of B-cell non-Hodgkin lymphomas. We recently reported the regression of splenic lymphoma with villous lymphocytes (SLVL) in patients with HCV after antiviral treatment, demonstrating a direct role of HCV in lymphomagenesis. This study expands our previous results in 18 patients with chronic HCV and SLVL. Mixed cryoglobulinemia (MC) was present in all cases and was symptomatic in 13 (72%). All patients were treated with interferon alone or in association with ribavirin. Hematologic and virologic responses were correlated. Fourteen (78%) patients achieved a sustained complete hematologic response after clearance of HCV RNA. Two patients had a virologic partial response and achieved a complete hematologic response. Two virologic nonresponders achieved partial hematologic response. Regardless of the response, monoclonal immunoglobulin gene rearrangement persisted after treatment. This study underscores the role of HCV in the lymphomagenesis and the benefit of antiviral treatment for patients presenting with HCV-driven lymphoproliferations.

Chronic lymphocytic leukemia (CLL) is characterized by a clonal expansion of low proliferating mature B and T lymphocytes in the bone marrow and peripheral blood. The nuclear antigen Ki 67 is a protein detected in G1, S, G2 and M phases of the cell cycle, but not in G0, and thus, is a widely accepted proliferation marker of Human tumors. The aim of this study was to evaluate Ki 67 monoclonal antibody in CLL. We studied 48 patients diagnosed as CLL on the presence of clinical signs, over 4.109/l circulating lymphoid cells and immunophenotyping by flow cytometry using CD19, CD5, CD22, CD23, FMC7 and immunoglobulin light chains monoclonal antibodies. Ki 67 immunostaining was determined by Avidin Biotin Complex method. Our results allows to characterize between CLL: one group which proliferation rate (percentage of Ki 67 positive cells) was equal or less than 2%, represented by 14 cases (29,2%) with morphological aspect of typical CLL, one group which proliferation rate was between 3% and 9% represented by 32 cases (66,6%) with morphological aspect of polymorph CLL or prolymphocytic leukemia, and a last group with proliferation rate equal or up to 10% and corresponding to two cases (4,2%) of transformation of CLL to high grade Non Hodgkin lymphoma. There were no correlation between Matutes immunological score and proliferation rate, as this rate was 2.9% in score < 3 and 2.7% in score > 3. This study confirm the Ki 67 usefulness in studying cellular proliferation, and underline that CLL with polymorphic cytology are more proliferate than typical CLL. These data reinforce the notion that CLL is a disease with heterogeneity in clinical behavior, immunophenotype, cytogenetic, molecular aspects, and thus, prognostic.

Acute promyelocytic leukemia (APL) is the most differentiated form of acute myeloid leukemia (AML) and has generally been considered to result from transformation of a committed myeloid progenitor. Paradoxically, APL has long been known to express the T-cell lymphoid marker, CD2. We searched for other parameters indicative of T-cell lymphoid specification in a cohort of 36 APL cases, revealing a frequent but asynchronous T-cell lymphoid program most marked in the hypogranular variant (M3v) subtype, with expression of PTCRA, sterile TCRA, and TCRG transcripts and TCRG rearrangement in association with sporadic cytoplasmic expression of CD3 or TdT proteins. Gene-expression profiling identified differentially expressed transcription factors that have been implicated in lymphopoiesis. These data carry implications for the hematopoietic progenitor targeted by the PML-RARA oncoprotein in APL and are suggestive of a different cellular origin for classic hypergranular (M3) and variant forms of the disease. They are also consistent with the existence and subsequent transformation of progenitor populations with lymphoid/myeloid potential.

cCD79a and IgH VDJ/DJ rearrangements are considered to be relatively specific for B lymphoid precursors. We looked for both in cCD3+, CD7+, CD19- T-ALLs classified by TCR status into alphabeta or gammadelta/immature (IM) lineages, with individualization of HOX11L2+ T-ALLs since they represent an intermediate alphabeta/gammadelta category. cCD79a was expressed at low levels in 47% of T-ALL and was most frequent in IMgamma T-ALLs. IgH rearrangements were common in gammadelta/IM (45%) and HOX11L2+ (35%) T-ALLs compared to HOX11L2-negative cases (3%; P<0.001). CD127 (IL7R alpha) expression was also more common in the gamma delta/IM lineage but its expression was virtually mutually exclusive of IgH rearrangement. Low-level cCD79a expression alone should therefore not be interpreted as evidence of B lineage affiliation in immature leukemias. gamma delta/IM lineage T-ALLs potentially include two distinct categories: predominantly IgH+, cCD79a+, CD127- cases which retain gamma delta and B lymphoid potential and IgH-, cCD79a-, CD127+ cases with restricted T lineage potential.

Red blood cell production depends on apoptosis rate of erythroid progenitors and precursors. This process is mainly regulated by the glycoprotein Erythropoietin (Epo), which positively regulates through the JAK/STAT5 pathway, in synergy with the transcription factor GATA-1, the expression of the antiapoptotic protein Bcl-XL. Thus, Epo starvation results in caspase-3 activation through the intrinsic mitochondrial pathway, and as a consequence GATA-1 is cleaved and apoptosis occurs. Recently we have shown that caspase-3 activation is also absolutely required for the morphological changes that occur during normal human terminal erythroid differentiation, including chromatin condensation as well as nucleus and cell size reduction. In this context, although activated caspase-3 colocalizes in the nucleus with GATA-1, apoptosis and GATA-1 cleavage do not occur (Zermati et al J exp med , 2001, 193; 247–254).

A 55‐year‐old Caribbean woman with a 6‐year history of smoldering adult T‐cell leukemia/lymphoma presented with clinical and biological symptoms of hemophagocytic syndrome. An extensive search for infectious diseases was negative. A lymph node biopsy showing large T‐cell lymphoma (CD4 − , CD25 + ) and findings of high LDH count and severe lymphocytosis led to the diagnosis of acute adult T‐cell leukemia/lymphoma. Anti‐retroviral therapy combining zidovudine, lamivudine, and interferon‐α was started, resulting in rapid control of both hemophagocytic syndrome and symptoms of acute adult T‐cell leukemia/lymphoma. Thus, we propose that adult T‐cell leukemia/lymphoma must be added to the spectrum of etiologies of hemophagocytic syndrome. Am. J. Hematol. 76:187–189, 2004. © 2004 Wiley‐Liss, Inc.

In acute myeloid leukemia (AML), coexpression of death receptors and ligands of the tumor necrosis factor (TNF) receptor/TNF-α superfamily on leukemic cells after chemotherapy is not always accompanied by apoptosis, suggesting that the apoptotic death receptor signaling pathway is disrupted. Because Fas-associated protein with death domain (FADD) is the main adaptor for transmitting the Fas, TNF-related apoptosis-inducing ligand receptors, and TNF receptor 1 death signal, expression of FADD was analyzed by Western blot and immunocytochemistry in leukemic cells of 70 de novo AML patients treated with the European Organization of Research and Treatment of Cancer AML-10 randomized trial before initiation of induction chemotherapy. Thirty seven percent of patients (17 of 46) with FADD negative/low (FADD−/low) leukemic cells had a primary refractory disease compared with 12% of FADD+ patients (3 of 24; P = 0.05). FADD−/low expression was significantly associated with a worse event-free survival [EFS (P = 0.04)] and overall survival (P = 0.04). In multivariate analysis, FADD−/low protein expression was independently associated with a poor EFS and overall survival (P = 0.002 and P = 0.026, respectively). Importantly, FADD−/low protein expression predicted poor EFS even in patients with standard- or good-risk AML (P = 0.009). Thus, we identified low or absent expression of the FADD protein in leukemic cells at diagnosis as a poor independent prognostic factor that can predict worse clinical outcome even for patients with standard- or good-risk AML.

Nodal mantle cell lymphoma (MCL) is a well-defined entity, but non-nodal leukemic cyclin D1 positive lymphoproliferative disorders have been reported and their relationship with MCL remains controversial and their prognosis heterogeneous. We prospectively studied the expression of cyclin D1 in CD5 positive leukemic B lymphoproliferative disorders at diagnosis and identified 65 cases overexpressing cyclin D1. We did not distinguish any clinical or biological criteria allowing one to identify a non-MCL group. Multivariate analysis identified age, anemia and p27kip1 expression as independent prognostic factors of survival. By univariate analysis, p27kip1 high expression proved to be the strongest predictor of prolonged survival. The median survival of p27 low expressors was 30 months, while it was not reached for p27 high expressors. A high level of p27 expression was often found associated with the absence of nodal involvement and the presence of somatic mutations, but neither of them was restricted to the p27 high expression group. In conclusion, we hypothesize that MCL and these cyclin D1 positive leukemic lymphoproliferative disorders represent a continuous spectrum of diseases. Determination of p27 expression level appears as a routine applicable test allowing identification of a subset of patients who could be considered for different therapeutic approaches.

BACKGROUND:Infective dermatitis (ID) is a rare dermatological condition of childhood that has been linked to human T-cell leukaemia/lymphoma virus type 1 (HTLV-1). Most cases have been reported in the Caribbean. Although several million people are estimated to be infected by HTLV-1 in sub-Saharan Africa, no case of ID has been reported in this area.OBJECTIVES:To identify and to describe cases of HTLV-1-associated ID in Senegal, West Africa.METHODS:Over a 3-year period, a serological test for HTLV-1 was performed at a dermatological centre in Dakar, Senegal, in children who presented with a picture suggestive of ID. Complementary haematological, immunological and virological investigations were performed in infected children and in their mothers.RESULTS:Five patients with typical HTLV-1-associated ID were identified, of ages 17, 5, 4, 3 and 3 years; two patients belonged to the same family. They all presented with repeated flares of superinfected dermatitis involving typical sites of ID (mainly the scalp, external ears, nares and eyelids), associated with nasal discharge, and less commonly with a nonspecific papular rash on the face or trunk. Although oral antibiotic therapy always gave effective control of the symptoms, recurrences were constant. A persisting dry dermatitis of the retroauricular folds was common between flares. Infection in the oldest patient was associated with a chronic adult T-cell leukaemia/lymphoma. The mothers of three patients, and the grandmother of another, were all infected by HTLV-1 strains belonging to the Cosmopolitan molecular subtype, with a perfect nucleotide identity of long-terminal repeat and env gp21 genomic regions within each family.CONCLUSIONS:We present the clinical and virological features of the first reported African cases of HTLV-1-associated ID. When compared with data from the Caribbean, infectious features seemed particularly prominent. ID appears to be overlooked in sub-Saharan Africa, where it might be easily confused with common pyoderma. Breast feeding appears to be the origin of HTLV-1 contamination of the children.

We have previously shown correction of X-linked severe combined immunodeficiency [SCID-X1, also known as gamma chain (gammac) deficiency] in 9 out of 10 patients by retrovirus-mediated gammac gene transfer into autologous CD34 bone marrow cells. However, almost 3 years after gene therapy, uncontrolled exponential clonal proliferation of mature T cells (with gammadelta+ or alphabeta+ T cell receptors) has occurred in the two youngest patients. Both patients' clones showed retrovirus vector integration in proximity to the LMO2 proto-oncogene promoter, leading to aberrant transcription and expression of LMO2. Thus, retrovirus vector insertion can trigger deregulated premalignant cell proliferation with unexpected frequency, most likely driven by retrovirus enhancer activity on the LMO2 gene promoter.

Introduction. – La lymphadénite histiocytaire nécrosante ou maladie de Kikuchi-Fujimoto est une entité anatomoclinique rare, d'étiologie inconnue dont le diagnostic est évoqué chez un adulte jeune, fréquemment de sexe féminin, présentant des adénopathies le plus souvent cervicales, une fièvre et une asthénie. La confirmation est apportée par l'étude histologique ganglionnaire. L'évolution est spontanément favorable, mais certains cas peuvent révéler ou évoluer vers un lupus cutané ou systémique.Exégèse. – Nous rapportons trois nouvelles observations de maladie de Kikuchi : un cas simulant un lupus systémique, un second avec une éruption cutanée de type lupique, et un cas sévère avec syndrome d'activation macrophagique dans le cadre d'une primo-infection EBV révélant un lupus érythémateux systémique.Conclusion. – La recherche d'une maladie lupique, imposant un suivi clinicobiologique de ces patients, est donc nécessaire et nous discutons les possibles liens physiopathologiques unissant ces deux entités.Introduction. – Histiocytic necrotizing lymphadenitis or Kikuchi-Fujimoto's disease is a rare anatomoclinical entity whose etiology remains unknown. It is mainly reported in young adult female, presenting with cervical lymphadenopathies, fever and asthenia. The diagnosis is based on the histological examination of a lymph node biopsy. The disease course is usually uneventful, but sometimes Kikuchi-Fujimoto's disease can reveal or evolve into a cutaneous or a systemic lupus.Exegesis. – We report three new cases of Kikuchi's disease: the first one mimicked a systemic lupus, the second one was associated with a lupus-like rash, and a the last one was a severe case with hemophagocytic syndrome and a primo-infection with Epstein-Barr virus revealing a systemic lupus erythematosus.Conclusion. – Clinical and biological follow-up of patients presenting with Kikuchi's disease is necessary to look for an association with a lupus. We discuss the pathogenic links between Kikuchi's disease and lupus.

T-acute lymphoblastic leukemias (T-ALLs) derive from human T-lymphoid precursors arrested at various early stages of development. Correlation of phenotype and T-cell receptor (TCR) status with RAG-1 and pTα transcription in 114 T-ALLs demonstrated that they largely reflect physiologic T-lymphoid development. Half the TCRαβ lineage T-ALLs expressed a pre-TCR, as evidenced by RAG-1, pTα, and cTCRβ expression, absence of TCRδ deletion, and a sCD3−, CD1a+, CD4/8 double-positive (DP) phenotype, in keeping with a population undergoing β selection. Most TCRγδ T-ALLs were pTα, terminal deoxynucleotidyl transferase (TdT), and RAG-1lo/neg, double-negative/single-positive (DN/SP), and demonstrated only TCRβ DJ rearrangement, whereas 40% were pTα, TdT, and RAG-1 positive, DP, and demonstrated TCRβ V(D)J rearrangement, with cTCRβ expression in proportion. As such they may correspond to TCRαβ lineage precursors selected by TCRγδ expression, to early γδ cells recently derived from a pTα+ common αβ/γδ precursor, or to a lineage-deregulated αβ/γδ intermediate. Approximately 30% of T-ALLs were sCD3/cTCRβ− and corresponded to nonrestricted thymic precursors because they expressed non–T-restricted markers such as CD34, CD13, CD33, and CD56 and were predominantly DN, CD1a, pTα, and RAG-1 low/negative, despite immature TCRδ and TCRγ rearrangements. TCR gene configuration identified progressive T-lymphoid restriction. T-ALLs, therefore, provide homogeneous expansions of minor human lymphoid precursor populations that can aid in the understanding of healthy human T-cell development.

Examination of bone marrow aspiration is an important tool in the diagnosis of haematological diseases. First attempts of bone marrow sampling took place at the beginning of the twentieth century. Thereafter, numerous methods were proposed and different materials were described. The commonly accepted sites for sampling are sternum and the iliac crest. We describe here a sampling procedure for each site. Bone marrow aspiration is a safely investigation, but not recommended for patients with impaired haemostasis. The physician must be aware of its side effects and complications which could occur. The consequence of the complications varies according to the type of iatrogenic injury. Prevention and rapid diagnosis are a crucial point in the management of bone marrow aspiration accidents. To avoid malpractice, the procedure should be taught by senior physicians including theoretical as well as practical learning. The purpose of the learning is a high quality of care to ensure patients the best comfort in subsequent bone marrow examinations, this point being particularly important in paediatrics.